AISI 316L (S31603) is an austenitic stainless steel for use in long-term and chloride-containing environments. The official name of this grade is UNS S31603. It is specially designed to offer higher performance and resist corroding elements better than standard 304 (L stands for Low Carbon).
Properties
AISI 316L has high strength, good fatigue strength and stress corrosion cracking resistance. It also has high resistance to pitting and crevice corrosion, which can occur in many organic and inorganic acids. The grade exhibits excellent mechanical properties at cryogenic temperatures and elevated temperature environments. It shows exceptional weldability when properly processed. This material also has excellent deep draw performance, making it a perfect choice for shaping and forming.
Uses
AISI 316L is used in a variety of industrial, architectural and construction applications. It is used in chemical and petrochemical processing equipment, laboratory equipment, valve and pump components and food processing and pharmaceutical equipment. In addition, it is often used in heat exchangers, plumbing systems and architectural panels. This material is also popularly used in medical and dental prosthetics, missile and aircraft components and cookware.
Fabrication
The fabrication of AISI 316L involves several steps. This material is cut using a variety of methods such as sawing, shearing or laser cutting. It is then formed by mechanical methods such as drawing, stamping, pressing or rolling. Next, the material is heat treated by either annealing or tempering. Finally, it is assembled, welded, machined, finished and inspected.
Welding
AISI 316L can be welded using all common arc and resistance welding methods, including shielded metal arc and gas tungsten arc welding. It is advised to use filler materials that provide a similar corrosion resistance and strength characteristics as the base metal during welding.
Cleaning and Finishing
AISI 316L is usually cleaned with a descaling or pickling solution and then finished with a variety of passivating or sealing processes. These may involve a coating, annealing, heat treatment or Post Weld Heat Treatment (PWHT).
Conclusion
AISI 316L is an austenitic stainless steel for use in long-term and chloride-containing environments. It has high strength, good fatigue strength, stress corrosion cracking resistance and excellent deep draw performance. It also has excellent weldability and is often used in a variety of industrial and construction applications. AISI 316L has to be cut, formed, heat treated, welded and finished with the right methods to give best results.